Studies on nitrate assimilation of Asphodelus aestivus Brot


Thesis Type: Postgraduate

Institution Of The Thesis: Uludağ Üniversitesi, Turkey

Approval Date: 2009

Thesis Language: Turkish

Student: FATMA SELCEN SAKAR

Supervisor: GÜRCAN GÜLERYÜZ

Abstract:

Asphodelus aestivus Brot. (A. microcarpus Viv.) is a perennial tuberous root geophyte of the family Liliaceae. Species spreads on slopes in agricultural lands, around the roads and calcareous soils in pastures all over the Mediterranean basin. In this study, nitrate reductase activity (NRA) in different compartments (tuberous roots, inflorescence stalks, leaves and flowers) of A. aestivus and actual mineral nitrogen (NO3 - and NH4 +) in soil surrounding the roots were investigated during a year. In addition, populations in different habitats were compared according to nitrate reductase activity (NRA) in different compartments and actual mineral nitrogen (NO3 - and NH4 +) in soil. Although the highest NRA was found in the leaves, the other plant compartments such as flower and tuberous roots have also nitrate assimilation capacity. The high nitrate assimilation capacity in suitable conditions is considered to be a good strategy in development and in dominancy of this species on Mediterranean environments. There was a seasonal variation model in nitrate assimilation in leaves and actual NO3 - content of soils. Depending on actual nitrate content of soils, nitrate assimilation increased in winter periods.